"extend" clearly has the highest priority, so it cannot be overridden. But that's not the problem by itself. The real trouble is a misuse of it. It looks like every person out there starts playing with syntaxes by adding "keepend" and "extend" almost everywhere. While "extend" should only be used for those very special elements that essentially "violate normal rules", like escape sequences or such.
In other words, every inner syntax region is already "extend" by default, so an outer region _may_ put "keepend" to it if needed. But the inner region _under exceptional circumstances_ still may overpower it all with "extend". Maybe, we could add yet another override specially for syntax-include but, imo, that could lead to even more confusion. Instead, we should better clean up existing syntax files from that garbage. So, in my opinion, the whole issue is a consequence of having many poorly written syntax files. Main distribution included. Kind regards, Matvey чт, 5 окт. 2023 г., 00:09 Edward McGuire <[email protected]>: > On Wednesday, October 4, 2023 at 1:55:55 PM UTC-5 Christian Brabandt wrote: > > Either nobody knows the answer or nobody understood the problem. > > Thank you Christian, I'm glad to know it got out there anyway. > > So maybe it will help for me to restate the problem, maybe not. > > This has to do with syntax highlighting when a file written in one > language has embedded in it a code block written in a different language. > The Vim distribution includes two great practical examples of how to do > this. > Both examples highlight the code inside the block using different syntax > rules than the code outside the block. > > One is in help document "syntax.txt" under the tag "sh-embed". > This shows how to extend the sh syntax so that embedded awk code is > highlighted using awk syntax. > > The other is syntax file "ant.vim", which has a powerful technique to > support multiple languages embedded in Ant syntax and highlight each > language using the correct syntax file. > > The problem I'm having is that sometimes code past the end of the block > gets highlighted using the syntax rules for the code inside the block. > > Here is an excerpt from the syntax I developed. > The excerpt highlights most of the buffer using the preinstalled "tex.vim". > Then, within any embedded code block introduced by a <<blockname>>= code > block introducer, and terminated by an @ or another <<blockname>>= code > block introducer, the embedded code block is highlighted by the > preinstalled "make.vim". > > syntax include @SyntaxTeX syntax/tex.vim > unlet b:current_syntax > syntax region Normal start=/\v%^/ end=/\v%$/ contains=@SyntaxTeX > syntax match nowebCodeChunkDeclarationMake > "\v^[<][<][mM]akefile(|\s.*)[>][>][=]\s*$" > \ skipnl > \ containedin=@SyntaxTeX > \ nextgroup=nowebCodeChunkBodyMake > highlight link nowebCodeChunkDeclarationMake PreProc > syntax include @SyntaxMake syntax/make.vim > unlet b:current_syntax > syntax region nowebCodeChunkBodyMake > \ keepend > \ start="\v.*" > \ end="\v^([@]($| ))|([<][<].*[>][>][=][ \t]*$)"me=s-1 > \ contained > \ contains=@SyntaxMake > > The key bit is the "keepend" keyword on the embedded code block. > It is there to force the block terminator to also terminate any contained > item. > It should stop the embedded language from reading past the block > terminator. > But the embedded language syntax can override this using "extend". > That can cause the embedded language syntax highlighting to continue past > the end of the code block delimiter. > And the problem seems to be that some of the preinstalled syntaxes do use > "extend". > > The question is how to prevent the preinstalled syntaxes from ever > highlighting past the end of the delimiter. > > -- > -- > You received this message from the "vim_use" maillist. > Do not top-post! Type your reply below the text you are replying to. > For more information, visit http://www.vim.org/maillist.php > > --- > You received this message because you are subscribed to the Google Groups > "vim_use" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/vim_use/7864bd47-6f44-42c5-8449-53e7740eae17n%40googlegroups.com > <https://groups.google.com/d/msgid/vim_use/7864bd47-6f44-42c5-8449-53e7740eae17n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- -- You received this message from the "vim_use" maillist. Do not top-post! Type your reply below the text you are replying to. For more information, visit http://www.vim.org/maillist.php --- You received this message because you are subscribed to the Google Groups "vim_use" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/vim_use/CAFsTB%2BKM0Sg8njdvXVuy2tdbu7vgZjmk1SQRn8EcoNmn6mLGqA%40mail.gmail.com.
